The biosynthesis and metabolism of the following natural products in the indicated species will be examined - nornicotine, alpha beta-dipyridyl, nicotelline (Nicotiana species); cocaine (Erythroxylon coca); scopolamine (Datura innoxia); meteloidine (Datura meteloides); ricinine (Ricinus communis); dioscorine (Dioscorea hispida); gramine (Phalaris species); azetidine-2-carboxylic acid (Convallaria majalis). Also aberrant biosynthesis involving 5-fluoronicotinic acid in several species will be examined. BIBLIOGRAPHIC REFERENCES: E. Leete and G.B. Bodem, Biosynthesis of shihunine in Dendrobium pierardii, J. Am. Chem. Soc., 98, in press, (1976). E. Leete and S. A. Slattery, The incorporation of (2-14C)- and (6-14C)-nicotinic acid into the tobacco alkaloids: Biosynthesis of anatabine and alpha, beta-dipyridyl, J. Am. Chem. Soc., 98, in press (1976).